My first approach was a flexible axis (a ptfe stick) or two copper sticks with an universal joint, that I can keep my stainless lid with the column adaptor in the center, and the agitator would come a little from the side. That was the reason, that I build the agitator with four instead of only two wings, I hoped, it would center better itself. But it didn't work well, so I thought, probably it's easier to build a new lid with the agitator in the center and the column beside it.

At first I drove it by a used rear wiper motor. Perhaps not the best choice, because rear wipers permanently change the direction of rotation. But I modified it, that it doesn't change. The good thing is: It is happy with a way smaller power supply than a front wiper. I ran it with 9V instead of 12V, so it became not so extreme hot during a long run. It consumes 8W at 9V. A front wiper will consume at 12V around 20W in the slow mode 35W in the fast mode (the fast mode is good for mashing probably). But generally wiper motors get very hot, when they run without headwind. Many homebrewers use them and say they can stand the heat. But still I decided to buy another motor. And yes, now it doesn't get as hot and rotates a bit faster without consuming more energy:http://www.pollin.de/shop/dt/MTM1OTg2OT ... links.htmlSorry, German online shop. But the link is good perhaps to get an idea. I run it with 5V, it consumes between 7W (distilling a thin mash) and 11W (mashing in grain).

Copper, stainless steel, Sn97Cu3 and special flux for ss. Two ss splint pin connections make it detachable. On the outside it's painted with a thick layer liquid zinc to prevent from electrical corrosion. I don't think this is necessary, but I had it at home.

There a two details, which help, that it is 100% leakproof:-metric copper pipes: An OD 10mm pipe fits exactly into an OD 12mm pipe.-The shaft bushing reaches into the mash, so there is no way out for the vapor, it's mash-sealed. Only mash could get out, but in practice only few drops. And this is easy to stop with some ptfe-tape.

When doing the first trials, it was leakproof even without the ptfe-tape. But the axis always got blocked in the bushing after a while. I sanded the axis down many times, now it was not 100% leakproof anymore without a seal. I did not find out, what the reason for the blocking was. Probably because the bushing is not absolute exact vertically, because the lid bent a bit while soldering (better I had spent extra money for copper instead of ss). So the wings bump at one side of the pot more often, what causes tensions. Sanding down the axis and bending the cross to a little smaller diameter solved the problem.Because of that I recommend to do the first runs with something, what doesn't need an agitator, tpw or spirit runs for example, if someone wants to build something similar. So if it blockes, you can finish the run without problems. And of course your first runs must be cleaning and a sac runs.

With the agitator I can distill single runs from thick fruit mashes on the pulp with my LM at maximum wattage (hotplate, 2.6kW, boiler filled with max. 13l). For potstill stripping whiskey on the grain perhaps too, but it is limited by foaming and puking and I don't want to make the batches smaller. I recently stripped from a 12l 100% rye flour mash (converted with enzymes, 10%abv) 4l low wines without scorching using 1.6kW all the time. Heat up and the first two liters 1h 20min, liters 3 and 4 50min.

To date, I have only stirred "manually". But with automation like this, it should simplify the process and also help with greater consistency (less variation between mashes). Couple this with an electric automated mashing system (eHerms), it should make us hobbiests capable of "commercial quality control".

Thanks.It's optimated for distilling. For mashing, a faster motor and smaller wings would be better. I have tried 12V for mashing in the grains, but the mash sloped out of the pot... And those large wings move the whole mash around at this speed, they don't mix it.

Ever try ebay? I usually find parts like this and they usually are a good bit less pricey. I "invented" an electric cup holder (years before Chrysler put them in their cars) with all ebay parts, except the heat sink which I got from a California company. I used it to this day in my office... hot coffee all day or 36*f soda.

I first had second hand wiper motors. But they work not very efficient. For this motor I paid 10 €+shipping in a German electronis online shop. Ebay normally has good prices here too. The most parts of my equipment I shoot there.

Okay, so this is really cool, but I'd love to know 1) do you notice a big difference in yield compared with straining? And 2) how loud is it? I imagine a lot of clanking, and I have highly noise-sensitive neighbors.

"A little learning is a dang'rous thing; Drink deep, or taste not the Pierian spring: There shallow draughts intoxicate the brain, And drinking largely sobers us again." - Alexander Pope

I never tried to strain corn or rye. Always distilled on the grain. Very slow of course because of the risk of scorching. So for me a big difference was speed. And I can strip longer without scorching it, for example 4l low wines from 10l mash, what gives a better taste IMO. Because it gets drier and drier it would scorch probably at the end of a long stripping run. And if I would distill a very thick mash in a single run without agitator, the cuts would smear. I recognized it with a very thick quince mash. I don't have numbers how much more yield you get. But when you don't strain you can use finer milled corn, what improves the yield too.

It's very silent when I strip a thick mash. Only a little more than the boiling sound. When I use it for spirit runs from low wines, it's louder. You hear it in the next room. But not in the room over or under you. But of course for distilling low wines, no agitator is needed normally.